Figure 16.10
GEO-GRAPHIC: Headward erosion. (A) Headward erosion begins as rainwater collects in low-lying areas to form rills and gullies. (B) The process of headward erosion is visible in this photo of the Namib Desert in Namibia. Note the gemsbok in the top center for scale.(B. © Pete McBride/National Geographic Image Collection/Alamy)